1. Technical Field
The present invention relates to transmission of information over an optical medium, and more particularly, to methods and systems that compensate for non-linear fiber-optics channel impairments.
2. Description of the Related Art
Service diversity, network functionalities, and transport capacities of photonics-enabled telecommunications have increased tremendously in recent years. Optical transmission at 100 Gb/s per wavelength has been under consideration and planning by network operators. At 100 Gb/s, optical fiber communications with conventional technologies face the technical challenges of strong signal degradation caused by transmission impairments, such as intra- and inner-channel nonlinearities, nonlinear phase noise and polarization-mode dispersion (PMD). In order to mitigate the signal distortions at ultra-high bit rates, some new technologies have been proposed and deployed in optical systems, and they represent a distinctive new trend in optical fiber communications. These new technologies include digital signal processing (DSP)-aided optical channel equalization, digital coherent reception, multilevel modulation formats and optical polarization multiplexing (or optical multiple input multiple output technologies).